Simple enough. But what happens when you live in a culture where green also means blue? (Before we answer that, here's why our own traffic light colors are red, yellow, and green.) That’s when ...

Red means “stop,” but what about blue? Drivers are noticing more than one stop sign color. Here’s where you might mind ...

Question: I’m wondering about a light that seems to only be on at night on the traffic lights. It’s a small purple or blueish light that’s near the traffic lights. I’ve tried to figure out what its ...